Method and apparatus to detect genuine or hoax contaminants

ABSTRACT

A system ( 100 ) and method for detecting contaminants in parcels or other mailings ( 110 ). The contaminants, either genuine or hoax, are detected using the system ( 100 ) that includes a jogger ( 140 ) that shakes the parcels or other mailings ( 110 ). The system ( 100 ) further comprises a particle sampler ( 170 ) that analyzes the air flow created over the parcels ( 110 ) while the parcels are shaken. The system ( 100 ) and method preferable includes a parcel opening cutter ( 120 ) and a ram ( 148 ) for compressing during the shaking of the parcels. The air flow is sampled in order to detect whether or not a plurality of opened parcels is suspected of including contaminants such as biological threat material.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to Provisional Application Ser.No. 60/373,003 entitled “DETECTION OF GENUINE AND HOAX BIOLOGICAL ANDNON-BIOLOGICAL CONTAMINANTS ON VARIOUS MEDIA”, filed on Apr. 16, 2002,the contents of which are incorporated herein by reference.

STATEMENT OF GOVERNMENTAL INTEREST

[0002] This invention was made with Government support under ContractNo. N00024-98-D-8124 awarded by the Department of the Navy. TheGovernment has certain rights in this invention.

BACKGROUND OF THE INVENTION

[0003] 1. Field of the Invention

[0004] The present invention generally relates to systems for handlingand screening parcels to detect contamination thereof, and applicationsthereof.

[0005] 2. Description of the Related Art

[0006] Numerous parcel handling systems have been developed and are inuse. The United States Postal Service (USPS) utilizes such systems tohandle the enormous quantity of parcels that are delivered each day bythe USPS. A notable feature, and an inherent disadvantage, of the USPSsystem is that the sender of a parcel can remain anonymous.

[0007] Following the terrorist attacks of Sep. 11, 2001, the U.S. mailwas utilized to propagate bioterrorist attacks upon high levelgovernmental representatives and important members of the media. Anumber of similar hoax attacks have followed and continue to this day.The ability of users of the USPS to remain anonymous has thwarted lawenforcement efforts to apprehend the bioterrorist(s).

[0008] The need for an apparatus and method for sanitizing parcels thatmay contain particles of biological contaminant, i.e. anthrax,non-biological contaminant, or other particulate matter or powders, thathave the ability to become airborne, has become apparent. Theoverwhelming volume of parcels handled by the USPS and other entities,however, has made it impossible to sanitize every parcel delivered.Nonetheless, following the bioterrorist attacks, the USPS began acampaign of irradiating parcels sent to persons and organization thatare likely terrorist targets.

[0009] Irradiation, however, is recognized as being an inadequatelong-term defense. Aside from entailing an unduly long time to irradiateparcels, the double digit kilogray doses that are needed to kill anthraxspores makes paper contained within the parcels brittle and smelly, andis fatal to film, magnetic media, electronic devices and prescriptiondrugs that are in the parcels that pass through the irradiatingmachines. The irradiation has also led to reports of sickness of theworkers at mail processing facilities.

[0010] A further shortcoming is that irradiation simply kills thecontaminant, and does nothing to identify contaminated parcels, such asenvelopes and boxes. Identification of contaminated parcels is anessential threshold requirement for law enforcement to identify andapprehend the terrorists.

[0011] Other techniques that can be used to sanitize suspect parcelsinclude the use of penetrative gamma rays or chemical sterilization,such as by use of chlorine dioxide gas. Each has its drawbacks. Use ofpenetrative gamma rays raises concerns of housing radioactive gammasources such as cobalt-60, and chlorine dioxide gas requires lengthyexposure time for adequate penetration of the parcels.

[0012] The techniques and apparatus known in the art either requireindividual treatment of the parcels or require prolonged exposure to thesterilization method.

[0013] While known techniques can sanitize parcels, the known techniquesfail to screen suspect parcels and cause an unacceptable processingdelay of such parcels. Further, the known techniques fail to identifysuspect parcels, as necessary to advance the efforts of authorities toapprehend the terrorists and hoax perpetrators.

SUMMARY OF THE INVENTION

[0014] The present invention provides the advantage of allowingreal-time screening of parcels for detection of possible contaminants.The screening can be performed either prior to or following irradiationor other parcel sterilization processes.

[0015] The present invention can be utilized to winnow the number ofparcels that must be subjected to irradiation or other sterilizationmeans, thereby accelerating the processing of the parcels.

[0016] Further, the present invention allows for timely screening ofpreviously irradiated parcels, wherein such additional screening isuseful in detecting parcels containing contaminant residue or powder orother hoax threat.

[0017] In accordance with one embodiment of the present invention, anapparatus that allows for rapid screening and identification of parcelslikely to contain biological or non-biological contaminants is providedcomprising a jogger for shaking a plurality of parcels, an air duct forchanneling an air flow over the plurality of parcels in the jogger, anda particulate sampler for analyzing the air flow to detect whether theplurality of opened parcels is likely to include contaminants.

[0018] In accordance with another embodiment of the present invention,an apparatus that allows for rapid screening and identification ofparcels likely to contain biological or non-biological contaminants isprovided comprising a cutter for opening each parcel, a jogger forshaking the opened parcels, an air duct for channeling an air flowobtained when the jogger shakes the parcels, and a particulate samplerconnected by the air duct to the jogger, wherein the particulate sampleranalyzes the air flow to detect whether the plurality of parcels islikely to include contaminants.

[0019] A method is also provided for rapid screening of parcels toidentify parcels likely to contain particles of biological ornon-biological contaminants, comprising the steps of shaking theparcels, creating an air flow over the parcels as the parcels areshaken, and analyzing the air flow to detect whether the parcels arelikely to include contaminants.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The following detailed description provides a betterunderstanding of the invention as well as other objects and furtherfeatures thereof, in which reference is made to the accompanyingdrawings, wherein:

[0021]FIG. 1 is a block diagram showing a preferred embodiment of thepresent invention;

[0022]FIG. 2 is a front perspective view of one embodiment of theapparatus 100 of the present invention;

[0023]FIG. 3 is a flowchart of a process for performing a totalparticulate count threshold detection;

[0024]FIG. 4 is a flowchart for performing detection utilizing aMultivariate Gaussian classifier;

[0025]FIG. 5a is a perspective view of the apparatus equipped with bothflats and first class mail joggers in accordance with the presentinvention;

[0026]FIG. 5b is a close-up view of a portion of the apparatus of FIG.5a;

[0027]FIG. 6a is a perspective view of a first class mail jogger used inthe apparatus; and

[0028]FIG. 6b is another perspective view of the first class mail joggerof FIG. 6a.

DETAILED DESCRIPTION OF THE INVENTION

[0029] The following detailed description of the invention will be madein reference to the accompanying drawings. In describing the invention,explanation of related functions or constructions known in the art areomitted for the sake of clearness in understanding the concept of theinvention, to avoid obscuring the invention with unnecessary detail.

[0030]FIG. 1 is a block diagram showing the various components of theapparatus 100. The parcels 110, a/k/a media, that are to be screenedinclude those which have an enclosed portion as well as parcels whichlack an enclosed portion. Examples of parcels 110 include, but are notlimited to, postcards, letters, envelopes, magazines and other flats(i.e. parcels containing unfolded material), as well as boxes. Theparcels 110, other than postcards and similar media that lack anenclosed portion, are, in a preferred embodiment, first opened by acutter 120.

[0031] After the cutter 120 opens the parcel 110, the parcel 110 isloaded into a jogger 140, which shakes the parcel 110, causing releaseof any particles contained within or on the parcel 110.

[0032] An air duct 165 connects with the jogger 140 and diverts anairflow 160 over the shaken parcel 110 to a particulate sampler 170,which notifies the operator of the apparatus 100, via an indicator alarm172, when the air flow 160 contains either a high concentration ofparticles or particles with suspect characteristics. The air flow 160over the parcels 110 in the jogger 140 is preferably created by aparticulate concentrator 190, which is located downstream from theparticulate sampler 170, drawing a vacuum on air duct 165, and mayalternatively be created by pressurizing the jogger 140.

[0033] Any parcels 110 that are in the jogger 140 when the indicatoralarm 172 sounds are identified as being suspect parcels 118. In theevent that an alarm is not received from indicator alarm 172, theparcels 110 in the jogger 140 are determined to be non-suspect parcels119.

[0034] Suspect parcels 118 are isolated for more detailed confirmatoryanalysis, such as PCR (polymerase chain reaction) analysis. Thisconfirmatory analysis is performed separately and will not cause delayof the inline, real-time screening process and method of the presentinvention.

[0035] The particulate concentrator 190 is equipped with a screen 192,as shown in FIG. 2. The screen 192 is preferably constructed in mannersimilar to that utilized to construct a dry-type high efficiencyparticulate air (HEPA) filter. The particulate concentrator 190captures, i.e. collects or concentrates, aerosolized particles which areejected from the parcel 110.

[0036] Each screen 192 is preferably provided with a unique identifierand is analyzed at periodic intervals, thereby providing a second-checkof the accuracy of the screening provided by the particulate sampler170. To facilitate the second-check capability of the analysis performedby the particulate sampler 170, parcels 110 which are found to benon-suspect parcels 119 are quarantined in groups corresponding to aspecific screen 192 that was in place at the time the non-suspectparcels 119 were screened. If the periodic analysis of the screen 192detects biological or non-biological contaminants during a time framewhen none of the parcels 110 were identified as being suspect parcels118, the entire quarantined group can either be re-screened or submittedfor further testing.

[0037] It will be recognized by those of skill in the art that thefunction of the dry-type filter of screens 192 which are depicted forillustrative purposes in FIG. 2 can be performed by other types ofconfirmatory analysis systems, such as a liquid or solid sampler unitswhich collect aerosolized particles, as well as by concentrator units.Also, in certain embodiments known in the art, particulate collectorsunits can also serve to act as concentrators. Accordingly, “particulateconcentrator” is used herein to mean concentrators, collectors and unitsthat acts as both concentrators and collectors.

[0038] The particulate concentrator 190 is arranged to capturerespirable particles, which present research indicates are generallythose particles between about 0.3 and 10 microns in size.

[0039]FIG. 2 is a front perspective view of one embodiment of theapparatus 100 of the present invention which includes a cutter 120, aflats jogger 142, an air duct 165, a particulate sampler 170, anindicator alarm 172 and a particulate concentrator 190.

[0040] The cutter 120, which is preferably integrated with the apparatus100, is a conventional letter opener that is preferably adapted tooperate as a corner cutter. The cutter 120 that is preferably includedin the apparatus 100 of the present invention comprises a conventionalcutter that has been modified to prolong blade life by reducing thelength of the slice made to each parcel 110. Accordingly, the cutter 120of the present invention slices open and removes one corner of eachparcel 110. The cutter 120 includes a blade/slicer 122 operationallyexposed on top of the cutter 120. Cutter guides 126 are provided toallow the operator to readily position the parcel 110 in the cutter.

[0041] Removal of the corner of the parcel 110 creates a defined pathfor egress of any contaminants within the parcel 110. Further, byslicing open only the corner, rather than slicing open an entire edge ofthe parcel 110, the integrity of the original seal of the parcel 110 ismaintained. This provides assurance to the recipient that the contentsof parcels 110 which are of a sensitive nature have not been compromisedby the screening process. Further, the unique corner cut left by thecutter 120 of the present invention serves as an identifiable indicationthat the parcel 110 has been screened for contaminants.

[0042] As shown in FIG. 2, the cutter 120 can be connected to a cornercollector 125 that vacuums away corners cut from the parcels 110,keeping the work table 130 of the apparatus clear of cutting debris.

[0043] In an alternative embodiment, the cutter 120 is modified topunch, rather than slice or cut, an opening in parcel 110. Such anembodiment is preferably used to screen parcels 110 such as boxes.

[0044] The present invention uses a modified conventional table toppaper jogger 140. Conventional paper joggers are utilized in mailroomand mail processing facilities to shake groups of parcels 110 into auniform alignment, creating a stack of parcels aligned along a commonedge. Conventional joggers include a frame 144 and an oscillating motor(not shown) which connects the frame 144 and a bin 141. When activated,the oscillating motor jogs, i.e. shakes and agitates, the parcels 110that are loaded in the bin 141 of the jogger 140. The shaking liberatesparticles contained in and on the parcel 110.

[0045] As shown in Table 1, the jogger 140 was successful in liberatingcontaminants when tested with various hoax materials and various letterpreparation methods (e.g. loose folded, etc.) when the parcels 110 wereshaken. TABLE 1 Hoax material 1 Hoax material 2 Hoax material 3 Firstprepara-  8% 15% 17% tion method Second pre- 13% 25% N/a paration methodThird prepara- 10% 16% N/a tion method Partial open- — 50% — ing created

[0046] The jogger shown in FIG. 2 is a flats jogger 142, which isessentially a conventional jogger that has been modified to include theair duct 165, air inlets 141 a, and a ram 148.

[0047] The ram 148 is a further preferred feature of the presentinvention. The ram 148 compresses the parcel 110 that is loaded in thebin 141, preferably at the same time that the parcel 110 is being shakenby the jogger 142. The compressing further assists in releasing anyparticles contained within the parcel 110. The ram 148 is preferablypneumatically actuated via pneumatic lines 148 a from a controller (notshown).

[0048] The air duct 165 shown in FIG. 2 channels the air flow 160 towardthe particulate sampler 170, which samples the particles in the air flow160. The particles in the air flow 160 are sampled in a real-time mannerto provide an essentially immediate indication of whether the parcels110 in bin 141 are suspected of being contaminated with genuine or hoaxbiological or non-biological contaminants.

[0049] The particulate sampler 170 can utilize one or a combination ofdetection methods, including absolute particle count detection, particlesize discriminatory detection, particle fluorescence detection and/orparticle fluorescence coupled with size detection. The particulatesampler 170 preferably utilizes a particle counter, such as thatmanufactured by Climet Instruments Company and sold under the CLiMET®trademark, to perform the detection of suspect parcels 118.

[0050] Initial testing indicated that certain types of parcels 110produce high background particle counts. For example, post cards werefound to produce a particle distribution that is highly concentrated inthe 1 to 5 micron size range. Such high background and other obscurantaerosols can produce unacceptable false alarms or mask the finding of acontaminated parcel. Such high background particle counts can beovercome by physically separating and processing in separate batchescertain types of parcels 110, e.g. postcards, known to have highbackground levels.

[0051] Predetermined characteristic signatures of contaminants and hoaxparticles can also be utilized by the particulate sampler 170. FIG. 3depicts a process for a performing threshold detection by comparing (instep 320) a total particle count (TPC) computed from the CLiMET data(step 310) with an acceptable threshold (T). Alternatively, oradditionally, as shown in the flowchart of FIG. 4, an MVG (MultivariateGaussian) classifier can analyze the CLiMET data. In step 410 the sizeof the particles in the air flow 160 is computed and the features of theparticles are extracted (step 420). A Mahalanobis Distance (D_(T)) isthen computed (step 430). In step 440, the computed D_(T) is compared toa previously computed Mahalanobis Distance (D) for clean, non-suspectparcels 119. A determination of whether the parcel 110 is a suspectparcel 118 or a non-suspect parcel 119 is then made.

[0052]FIG. 5a is a perspective view of an embodiment of the apparatus100 equipped with a flats jogger 142 and a first class mail jogger 146located on opposite sides of the cutter 120. The apparatus 100 of FIG.5a has separate particulate scanners 170 for each jogger. The close-upperspective view provided in FIG. 5b provides a more detailed view ofthe particulate scanner 170 that functions with the first class mailjogger 146 and other components of the apparatus 100.

[0053] Also shown on FIGS. 2, 5a and 5 b is a translucent hood 180 thatprotects the operator and other personnel from inadvertent contaminationby contaminants released by the cutter 120 or the jogger(s). FIG. 5aalso shows a manifold 195 that is utilized to connect the apparatus 100to an external air filtration system that preferably places theapparatus 100 under a slight negative atmospheric pressure, therebypulling the contaminants away from the operator. Preferably, for theembodiment shown in FIGS. 5a and 5 b, each particulate concentrator 190draws approximately 27 cfm (cubic feet per minute) and the manifold 195draws between approximately 1,100 and 1,500 cfm.

[0054] The first class mail jogger 146 shown in FIG. 4a is shown infurther detail in FIGS. 6a and 6 b.

[0055] The first class mail jogger 146 is constructed to accommodate aplurality of similarly sized parcels 110, typically folded first classmail in standard size business envelops juxtaposed positioned in the bin141. The ram 148 of the first class jogger 146 travels in a longitudinaldirection, applying compressive force toward the port 155.

[0056] The flats jogger 142 more readily accommodates flat parcels 110.In contrast to the sideward stroke of the ram 148 of the first classmail jogger 146, the ram 148 of the flats jogger 142 has a front to backstroke, moving toward the rear of the apparatus 100. It was found to bepreferable to extract the air flow 160 from the flats jogger 142 at aslightly higher velocity than from the first class mail jogger 146.

[0057] Although the preferred embodiments include a cutter 120 forinitially creating an opening in each parcel 110, it has been observedthat the present invention be utilized to screen parcels without thecutter 120.

[0058] Although the preferred embodiments of the present invention havebeen disclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

What is claimed is:
 1. An apparatus for rapid screening of parcels toidentify parcels likely to contain biological or non-biologicalcontaminants, comprising: a jogger for shaking a plurality of parcels;an air duct for channeling an air flow over the plurality of parcels inthe jogger; and a particulate sampler for analyzing the air flow todetect whether the plurality of parcels is likely to includecontaminants.
 2. The apparatus of claim 1, further comprising aparticulate concentrator for filtering the air flow.
 3. The apparatus ofclaim 2, wherein the particulate concentrator includes a particulate airfilter which is analyzed at periodic intervals to confirm the accuracyof the analysis performed by the particulate sampler.
 4. The apparatusof claim 1, wherein the jogger further comprises a ram that compressesthe parcels.
 5. The apparatus of claim 4, wherein the ram is fixablyattached to a push plate which contacts one of a plurality of parcelsjuxtaposed positioned in a bin of the jogger.
 6. An apparatus for rapidscreening of parcels to identify parcels likely to contain biological ornon-biological contaminants, comprising: a cutter for opening eachparcel; a jogger for shaking the opened parcels; an air duct forchanneling an air flow obtained when the jogger shakes the openedparcels; and a particulate sampler connected by the air duct to thejogger, wherein the particulate sampler analyzes the air flow to detectwhether the plurality of opened parcels is likely to includecontaminants.
 7. The apparatus of claim 6, further comprising a hoodwhich covers the jogger and the cutter.
 8. The apparatus of claim 6,wherein the jogger includes a bin capable of holding a plurality ofparcels.
 9. The apparatus of claim 8, wherein the jogger furtherincludes a cover that covers parcels loaded into the bin.
 10. Theapparatus of claim 6, wherein the cutter slits open a corner of eachparcel.
 11. The apparatus of claim 6, wherein the cutter punches a holein each parcel.
 12. The apparatus of claim 6, wherein the jogger furthercomprises a ram for compressing the parcels.
 13. A method for rapidscreening of parcels to identify parcels likely to contain particles ofbiological or non-biological contaminants, comprising the steps of:opening each parcel; shaking the parcels; creating an air flow over theparcels as the parcels are shaken; and analyzing the air flow to detectwhether the parcels are likely to include contaminants.
 14. The methodof claim 13, wherein the shaking step further comprises compressing theparcels.
 15. The method of claim 13, wherein as the parcels aresimultaneously shaken and compressed.
 16. The method of claim 13,further comprising the steps of: filtering the air flow with aparticulate concentrator; and, performing a confirmatory analysis on theparticulate concentrator.
 17. An apparatus for rapid screening ofparcels to identify parcels likely to contain biological ornon-biological contaminants, comprising: a jogger for shaking aplurality of parcels; an air duct for channeling an air flow over theplurality of parcels in the jogger; and a particulate concentrator forfiltering the air flow, wherein the particulate concentrator is analyzedat periodic intervals to analyze the air flow to detect whether theplurality of parcels is likely to include contaminants.
 18. Theapparatus of claim 17, further comprising a cutter for opening eachparcel prior to the shaking of the parcels.